初中化学“物质分离与提纯”的项目式教学设计——保护滇池母亲湖争做小小水质检测员

Project-based Teaching Design of“Separation and Purification of Substances”in Junior High School Chemistry——Protecting the Mother Lake Dianchi and Being a Little Water Quality Inspector

以滇池水质的检测和净化为项目核心,开展初中化学关于物质分离与提纯的教学。通过“取水、确定检测指标”“探究如何降低滇池水的色度”“探索如何降低滇池水的电导率”等三个子项目来帮助学生构建物质分离和提纯的思维模型。利用手持技术数字化实验,测定了滇池水质指标,并与蒸馏水进行对比,从定性和定量两个角度来探究滇池水质净化的效果。学生从滇池水质的检测到净化过程中解决了一系列复杂的问题,在此过程中发展了“结构—性质—用途”的重要化学观念、科学思维、科学探究与实践,以及“树立生态文明理念”的科学态度与责任等化学学科核心素养。

The detection and purification of Dianchi water is the core of a project to teach junior high school chemistry about the separation and purification of substances.The students were given three sub-projects:“taking water and determining the testing indexes”,“exploring how to reduce the colour of Dianchi water”and“exploring how to reduce the conductivity of Dianchi water”to help the students to build a model of thinking about the separation and purification of substances.This project uses handheld technology to digitally measure the quality of Dianchi water and compare it to distilled water,exploring the effects of Dianchi water purification from both qualitative and quantitative perspectives.Students solved a series of complex problems from the detection to the purification of Dianchi water,and in the process developed important chemical concepts of“structure-property-use”,scientific thinking,scientific investigation and practice,and the concept of“establishing the concept of ecological civilisation”.Establishing the concept of ecological civilisation,scientific attitude and responsibility,and other core qualities of chemistry.